Best Season/ Weather in Bhutan
The temperature in Bhutan drops noticeably as one travels from the lower altitudes in the south to the high Himalayan regions in the north. The southern border areas are the hottest and have tropical conditions. Mercury rises above 30 °C in summer (mid May to August) though in winter (December to February) it dips to about 15 °C. Northern regions experience severe winters and mild summers (average temperatures range from 0 °C to 10 °C) with snow a permanent feature in areas bordering Tibet. In the central regions of Bhutan, a pleasant temperate climate is the norm throughout the year.
Autumn (late September through November) is the best time to visit Bhutan. The weather in Bhutan at this time is ideal for trekking and sightseeing, there is a lot of sunshine and very little rain. This is also the time when many colourful traditional festivals are held. Spring (March to May), when the country looks at its vibrant best, is another popular tourist season. Flowers are in full bloom and the weather is good.
Though showers can occur any time of the year in Bhutan, it really pours during the monsoon season (June to September) which coincides with the summer. Humidity is high, particularly in the southern regions and flash floods and landslides are not uncommon.